The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 05, 2013
Filed:
Nov. 04, 2010
Haiyang Yin, Kitchener, CA;
Valentina Iqorevna Kramarenko, Toronto, CA;
Haiyang Yin, Kitchener, CA;
Valentina Iqorevna Kramarenko, Toronto, CA;
Research In Motion Limited, Waterloo, CA;
Abstract
Control and status information between a mobile device and another device can be signaled over a voice channel using DTMF tones, e.g., a pre-defined sequence of DTMF tones can signal a desired message (more generally, a feature code). Tones sent are separated from each other by a time gap (Ttimer). If a receiving device does not receive a sequence of DTMF tones that can be matched to stored definitions of feature codes, then the receiving device generates a negative ACK. Also, if the sending device does not receive either negative or positive ACK, then sending device resends all tones of the feature code after a retry delay (Ttimer). Rather than having the Ttimer start when tones for a feature code start to be transmitted, the Ttimer is started after the Ttimer expires for the last tone of a feature code. Thus, only one timer is running (either Tor T), rather than having multiple timers running concurrently. Race conditions between the timers are avoided.